Scriber and roller guide skin marker gage



Aug. 26, 1958 R. R. KlENLE 2,848,813

SCRIBER AND ROLLER GUIDE SKIN MARKER GAGE Filed May '7, 1956 IN VEN 7'01? R. R. K/ENL E ATTORNEY Patented Aug. 26, 1958 SCRIBER AND ROLLER GUIDE SKIN MARKER GAGE This invention relates to a scriber and roller marker skin marker gage used for accurately fitting the sheets making up the metal skins of, for example aircraft, so that the assembled sheets will have a smooth uniform overall surface.

An object of the invention is to provide a tool for quickly and accurately marking the line along which a sheet of metal must be cut to conform to the edge of a prior installed sheet against which the sheet to be installed must be an accurate fit.

Afurther object of the invention is to provide a scriber gage which permits the sheet, to be scribed, to be tied down more closely in overlapping edge relation with the installed sheet due to the decreased friction involved in the use of the gage resulting from the provision of a roller and a skip guide bearing against the installed sheet and the supporting frame structure, respectively.

Still a further object is to provide a scriber gage in which the desired gap between the installed and the tobe-installed sheet can readily be adjusted by the insertion or removal of shims or spacers between the scriber per se and its supporting block on the gage thereby displacing the center line of the scriber relative to the roller periphery.

Particularly in the manufacture of aircraft, one of the problems has been accurately to fit the successive metal sheets, for example of aluminum plate, with proper and uniform intervening gaps therebetween onto the supporting frame, so that both excessive and insuflicient gaps between the edges of the adjacent sheets are alike avoided, as also any edge irregularities in the exterior surfaces of the sheets after installation. It is obvious that metal sheets as supplied do not have exactly the same dimensions since the cost thereof would be prohibitive, and also are not true flats. Furthermore, not all edges to be fitted are uniformly straight edges, with which such stock sheets are delivered, but may be curved, and hence succeeding sheets must be cut accurately to fit not only smoothly over the frame portion they are intended to cover but also to. fit the exposed edge of the sheet previously installed. The edge of the next sheet to be fitted must hence be trimmed so that such edge conforms exactly to the exposed edge. Before such trimming can be had, such edge of the next sheet must be accurately marked by tracing thereon the outline of the exposed edge.

I accomplish the foregoing, and other, objects with the scriber tool of the instant invention by providing a clamp consisting of two superimposed leaf springs having a spacer therebetween at one end. The end region with such spacer may be of such a length as to serve as the gage handle, or, as in an alternative embodiment, may be short and a separate handle provided for the gage. On the free end of the upper leaf I provide a scriber having a diamond shaped point or tip which extends downwardly toward the lower leaf and, preferably, extends into a registering aperture of such dimensions that the point region per se does not engage the lower leaf when the gageis not in actual use. The free end of the lower leaf, which extends beyond the upper leaf, on such extending portion has a pin extending downwardly with a roller rotatably thereon, the pin being parallel to the center line of the scriber per se but offset therefrom. The rotatable roller is of such diameter that its top surface. extends laterally beyond the vertical extension of the scriber center line and acts as a support below the tip during the scribing of an interposed metal sheet. I provide a guide for the roller spaced therefrom and having its lowermost region slightly below the bottom surface of the roller and readily slidable thus enabling the roller readily to skip over shims, tooling holes, frame joints, etc. In one embodiment this skip guide is an integral lip reentrantly pending downwardly from the roller end of the lower leaf; in a second, it is a loop angularly positioned about the roller with the ends thereof mounted in the lower leaf and its closed region lowermost; while in a third embodiment it is a spherical, spheroidal or oval upset of the bottom end of the pin on which the roller is rotatably mounted.

The scriber tool of 'my instant invention will be more accurately understood from the following detailed description of two illustrative embodiments, and a modification, thereof in connection with the appended drawing in which:

Figure 1 is a top view of the first illustrative embodiment of the scriber and roller guide skin marker gage of my invention;

Figures 2 and 3 are a side, and a front, elevational view of such first illustrative embodiment;

Figures 4 and 5 are a side, and a front, elevational view respectively of a second illustrative embodiment. thereof; and

Figure 6 is a side elevational view of an alternative roller and skip guide arrangement for use in both embodiments.

In the first illustrative embodiment, shown in Figures 1, 2 and 3, the upper spring leaf 1, of spring steel for example, is permanently aifixed at one end to the spacer block 2 and the lower spring leaf 3 by any desired means, for example, a plurality of bolts 4. Both leaf springs 1 and 3 are flat, being straight for somewhat more than half their lengths from the spacer block end and bent downwardly, the upper leaf for example 30 and. the lower leaf somewhat more, for example 35, and then bent back again so that their free end regions lie in planes parallel to those of their interconnected ends. The spacer block 2 has a length about one-fourth, and the downwardly bent intermediate region of both leaf springs is likewise about one-fourth, the length of the upper spring leaf 1. The free end regions of both springs are. of progressively less width, While the interconnected ends and the intermediate bent regions are of uniform width. A threaded bolt 5 extends through an aperture in leaves 1 and 3 at some distance from the spacer block 2 but before the initial bend of the intermediate leaf regions, and a washer 6, or a plurality of them between the two leaves and about the bolt. 5., may be tightened .up by nut 7 on bolt 5 to adjust the degree of separation and springiness of the leaves.

To the upper surfaces of the free end of the upper leaf 1 a metal block 8 is integrally attached with one face thereof registering with the free end edge 9 of leaf 1. A tool steel scriber 10 of rectangular cross section and shape and having a diamond shaped point 11 is attached, as by the screws 12, to the end face of block 8 so that it lies tight against such block and face and the leaf end surface 9, at times as hereinafter described with one or more shims 18 therebetween, with the scriber 3 1 point or tip 11 extending downwardly. The normal spacing at the free ends of leaves 1 and 3 is such that the scriber tip 11 extends part way into an aperture 13 in the lower leaf 3 for the purpose of protecting the scriber point per selfrom unnecessary blunting when the tool is not in use. The free end regions 14 of the lower leaf 3 are rounded progressively from the bottom to the top surface of such leaf, toassist in holding the gage and sliding it over obstructions. encountered in use.

Rotatably supported on a stepped pin 15 extending downwardly from the lower leaf 3 at the region thereof extending beyond the upper leaf 1, a roller 16 is so positioned that the portion thereof vertically the nearer to the extended center line of the scriber overlaps such center line extension and is the more remote from the free leaf end. The extreme end portion of the lower leaf is bent downwardly to form 'a lip of tapering width withits narrowest and rounded portion somewhat below the plane of the bottom of the roller. In the instant skip guide, that is lip 17, as in the other forms of the skip guide shown in the second embodiment and in Fig- .ure 6, the lower surface of the skip guide is of the order of about 0.04 inch below the bottom of the roller.

In use, the scriber and roller guide skin marker gage of the first embodiment is grasped at the portion thereof between the end where the leaves are interconnected and the adjusting bolt 5, which portion, as has been stated, forms a convenient handle. The metal sheet to be marked is positioned and tied down with temporary hardware with an edge region overlapping the edge of the installed sheet to which it is to be fitted. The free end of the scriber tool is placed against an edge lateral to the overlapping edge of the sheet which is to be scribed so that the sheet to be scribed rests on the lower leaf and against one of the lateral and inclined faces of the scriber point 11. When the tool is now drawn onto the sheet, the metal sheet readily removes the scriber tip from its aperture 13 and positions the tip 11 on the upper face of the sheet. Roller 16 is then brought against the installed edge and the tool drawn therealong with the roller against such edge and the skip guide spacing the bottom of the roller from any obstruction, etc., thus marking exactly the contour of the installed edge on the sheet to be fitted at exactly the required spacing. In drawing the tool along, it will be noted that the rounded lower edge of lip 17 will ride on any frame member that may be below the installed sheet slightly to space the bottom of the pin and roller therefrom, thus facilitating the drawing of the tool along the installed edge'with the roller in engagement with such edge. lip 17 will readily slip and skip over gaps, shims, etc., and will not catch therein. Many of the metal sheets have to be fitted to curved surfaces, and the instant scriber tool of my invention is particularly adapted for scribing such, both by permitting closer tying down of the sheet to be fitted for scribing and because of reduced friction as compared to prior art scribers.

The gap between the installed edge and the scribed edge is obviously also determined by the horizontal distance between the. center line of the scriber 10 and the cylindrical surface of the roller 16, indicated by d in Figures 2, 4 and 6. In the embodiments herein illustrated, I have made of the order of 0.01 inch, that is, with the scriber directlymounted against the block 8 and the end surface 9 by means. of the screw bolts 12. T o vary d, I remove the screws 12 and insert one or more shims 18 of any desired width between the block 8 and the scriber 10, and replace and tighten bolts 12. Thus gaps of any desired and practical distance between the installed and the to-be-installed edge may be accurately scribed with one and the same gage.

In the second illustrative embodiment, shown in Figures 4 and 5, the upper and lower leaves, 20 and 21, areconsiderably shorter than those of the first embodiment just described. The instant embodiment is par- The ticularly useful in places where space requirements necessitate a shorter tool, and since their shortness does not permit using the leaf springs as a handle, I provide a handle 22 extending substantially the length of the gage attached to the upper leaf 20 at the interconnected ends of the leaves and freely above the free leaf ends to permit of maximum separation of 'the free leaf ends from each other in mounting the gage on the sheets to be scribed. At one end the leaves 20 and 21 are likewise afiixed to a spacer 23, narrower than is the spacer 2 of the first embodiment, and otherwise the instant second embodiment may be of the same construction as the first embodiment of Figures 1 through 3, as is indicated by the use of the same reference characters in Figures 4 and 5 for identical elements as in the first embodiment. In this second embodiment I position the tension adjusting bolt 29 in the intermediate bent region of the leaves, and incorporate a slight modification in the free end region of the lower spring 21. The free'end of the lower leaf is not bent downwardly to form a lip 17 as is leaf 3 of the first embodiment. To provide the clearance between the bottom surface of the roller-16 and pin-17 and any frame support below the installed edge, the skip guide is in the form of a wire loop 24 aifixed at its ends in leaf 21 and extending angularly downward from the side of. the roller more remote from the free end of the lower spring to'in front of the roller side adjacent to the free end of the lower spring, straddling the roller to alllow free rotation of the roller, with the lower loop portion somewhat below, as above stated, both the pin 15 and the roller 16. I attach the ends of the loop 24 to the leaf 21 so that the central longitudinal axes are aligned vertically. In Figures 4 and 5 the loop 24 is shown spaced away from and extending further below the roller than it actually does for ease of illustration; in the actual embodiment the lower surface of the loop is a distance below the roller of the same order, i. e., 0.04 inch, as is the'lip 17 of the first embodiment. Obviously, the lip 17 of the first illustrative embodiment may be replaced by the loop 24 of the second illustrative embodimenhiand-vice versa.

Still another form of the skip guide for use with either embodiment of the scriber gage of my instant invention, is that shown in Figure 6 in which the free end portion of the lower leaf 21 and the scriber 10, both in part, are shown relative to the pin and roller assembly, and the pin'incorporates the skip guide. The roller pin 25 is again afiixed extending downwardly from the lower leaf 21 near its free end, and has its lower end 26 upset to form a spheroidal, spherical or oval head of a diameter exceeding that of the main body of the pin. Roller 27, which is preferably ball bearing mounted on pin 25, has a recessed end portion 28 adapted to receive the adjacent upper portion of the upset head 26. It will be noted that the central portion of the upset head 26 remains below the lower face of the roller 27 and functions as a skip guide.

Various modifications of the scriber and guide roller skin marking gage of my invention will suggest themselves to the skilled worker in the art. The embodiments I do show and discuss are solely by way of illustration and are in no manner to be regarded as in any limiting sense.

What I claim is:

l. A scriber tool for sheet metal comprising an upper metal spring leaf, a lower metal spring leaf of a length greater than that of the upper leaf, a spacer at one end region of and between the leaves, means aflixing the leaves to the spacer in superimposed longitudinal alignment, :1 tool block at the free end region of the upper leaf, a diamond pointed scriber detachably affixed to the tool block to extend with its scriber point downwardly to the-lower leaf, a pin projecting downward from-the region of the lower leaf extending beyond the upper free leaf end, a

roller rotatably supported on the pin and of a diameter so that the end surfaces of the roller vertically overlap the scriber point, and a skip guide supported on the lower leaf extending to slightly below the bottom of the roller.

2. A scriber tool according to claim 1 in which the lower leaf is provided with an aperture aligned with the point of the scriber tool to support the region about the scriber point on the lower leaf with the point per se free within the aperture when the tool is not in use.

3. A scriber tool according to claim 1 in which the skip guide comprises the free end of the lower leaf which is formed to a tapering rounded edge bent downwardly reentrantly toward the roller so that its narrowest portion is below the bottom of the roller and the roller pin and is closely adjacent the cylindrical surface of the roller.

4. A scriber tool according to claim 1 in which the skip guide comprises a loop spaced closely about the cylindrical surface of the roller, the ends of the loop are anchored in the lower leaf and extend angularly downward with the lowermost closed loop portion slighty below the bottom of the roller and of the roller pin.

5 A scriber tool according to claim 1 in which the skip guide is an ovaloid upset integral with the bottom of the pin about which the roller is rotatable, the central portion of the upset being slightly below the bottom of the roller.

6. A scriber tool according to claim 1 in which the end regions of each leaf lie in parallel planes and the region thereof intermediate the end regions inclines from the plane of one end region to that of the other end region.

7. A scriber tool according to claim 1 in which the end regions of each leaf lie in parallel planes and the region thereof intermediate the end regions inclines at an angle of at least about 30 degrees from the plane of one end region to that of the other end region, the inclinaation of the intermediate region of the upper leaf being less than that of the lower leaf.

8. A scriber tool according to claim 1 in which a handle is attached to the upper leaf between the regions thereof adjacent to the spacer and the tool block.

9. A scriber tool for sheet metal comprising a first elongated leaf of spring metal of predetermined length, a second elongated leaf of spring metal of a length exceeding the predetermined length, a spacer between the leaves at one end region thereof and afiixed thereto with the end surfaces of each leaf in alignment, the said one end region being substantially half the predetermined length and the spacer being of a length less than half that of said one end region of the leaves and positioned with one surface in substantial alignment with the aligned ends of the leaves, an intermediate region of each leaf of about one-fourth the predetermined length, said one end region being in planes parallel to those of the other end region of the leaves, the intermediate region being substantially straight and inclined from the planes of said one end region to those of said other end region, the intermediate region of the second leaf having a greater inclination than has the intermediate region of the first leaf, means positioned longitudinally between the spacer and the nearer end of the intermediate regions to adjust the spacing between the free other ends of the leaves, a supporting lock integrally on the surface of the first leaf remote from the second leaf having a fiat end surface aligned with the free end surface of the first leaf, a pointed scriber afiixed to the flat end surface of the block with its point extending to the second leaf, an aperture in the second leaf aligned with the scriber and adapted to receive therewithin the point of the scriber, the edges of the aperture engaging regions of the scriber near the point thereof, a pin integrally supported in the region of the second leaf extending longitudinally beyond the first leaf, said pin extending in the direction away from the first leaf, a roller rotatably supported on the pin with its upper flat surface adjacent to the lower surface of the second leaf and having a diameter of such magnitude that the upper roller surface overlaps the point of the scriber, and means supported by the second leaf extending to a region closely adjacent to the cylindrical surface of the roller and to below the roller and the pin.

10. A scriber tool for sheet metal comprising an upper metal spring leaf, a lower metal spring leaf of a length greater than that of the upper leaf, a spacer at one end region of and between the two leaves, means affixing the leaves to the spacer in superimposed longitudinal alignment, an aperture in the lower spring leaf, a tool block at the upper leaf free end region, a diamond pointed scriber detachably affixed to the tool block and extending with its point downwardly, the scriber point region being pyramidal and formed by a plurality of flat surfaces at an acute angle to the plane of the lower spring leaf, the upper spring leaf pressing the scriber with its point into the aperture a distance less than the thickness of the lower spring leaf so that a region adjacent to the point of the flat surfaces rests on the aperture edges with the point per se free, each fiat surface of the plurality having a length such that the exposed height thereof above the lower leaf spring with the point in the aperture is of the order of thickness of the sheet to be scribed, a pin projecting downward from the region of the lower leaf extending beyond the upper free leaf end, a roller rotatably supported on the pin and of a diameter so that the end surfaces of the roller vertically overlap the scriber point, and a skip guide supported on the lower leaf extending to slightly below the bottom of the roller and of the pin.

References Cited in the file of this patent UNITED STATES PATENTS 1,179,706 Doerr Apr. 18, 1916 1,593,321 Wiegand July 20, 1926 2,287,601 Callaghan June 23, 1942 2,305,065 Corkish Dec. 15, 1942 2,409,106 Connelly Oct. 8, 1946 2,430,025 Mattias et a1. Nov. 4, 1947 2,557,148 Schimmel June 19, 1951 2,557,699 Silver' June 19, 1951 2,654,953 Phelps Oct. 13, 1953 FOREIGN PATENTS 270,712 Germany Feb. 24, 1914 506,578 Belgium Nov. 14, 1951 

